1. Field of the Invention
The present invention relates to a super-slim touch keyboard for a tablet PC and a super-slim smart cover device mounting a mobile terminal and serving as a keyboard.
2. Discussion of Related Art
A keyboard is an input device of a computer system and configured with letters, numbers, special characters, and function keys. The number of keys on the keyboards is currently increasing according to users' demand for function expansion, and, in general, a total of about 100 keys on the keyboards are used.
The function keys may include Ctrl, Alt, Shift, Enter, and Tab, which are used for the purpose of changing an original meaning of a key, controlling program operation, or moving text or cursor on the monitor.
An operating mechanism of the keyboard is classified into a mechanical operation and electronic operation according to a method of flowing currents. In the electronic operation, when a key is pressed, a spring in the key is compressed, then the amount of charge flowing through a circuit connected to the key is decreased, and the circuit identifies the status of a key press by measuring the amount of charge flowing through the current. In the mechanical operation, when a key is pressed, currents flows by two metals being attached and detached and the circuit identifies the status of a key press by determining whether the current flows or not.
However, such electronic and mechanical keyboards may not be suitable to use in a notebook PC or related products, which have recently become slimmer.
Meanwhile, a mobile terminal basically functions as a telephone performing voice or video communication with the other parties while a user thereof always carries it. In addition, the mobile terminal may provide a variety of functions, such as a camera function, a video player function, a schedule management function, an information search function using a wireless internet, and a gaming function.
In normal mobile terminals, various key buttons may be provided for users to select a specific item or input numbers or letters.
Recently, as a data processing speed and a storage capacity of a mobile terminal have been enhanced, there is a limit in that the mobile terminal accommodates various functions the users require with only the key buttons installed therein.
Mobile terminals, such as iPad® or Galaxy tab®, recently being commercialized, are thin, a rear side thereof is protected by an aluminum case, and a front side thereof is used as a display portion. In addition, a support configured to protect the display portion and support the display portion in an upright position is commercially available.
However, since such a support simply supports the mobile terminal, and does not function as a keyboard, the portable terminal may be used only for an audiovisual purpose, and thus input functions may be reduced.